I'm not sure if this has been tossed around before, but I would like to suggest changing the visuals of the 2 piece Monster Set, Earthgore's healing proc.
For those of you unaware, Earthgore is a Monster Set that, when a nearby ally drops to a low health percentage, it will autocast a healing circle on them.
The healing circle is a dark red blood cloud, raining blood.
I can't count how many times in PuG groups of various levels, I've had to explain this -- and assure them that I'm not trolling. It's tiresome, and frankly it's not something I can groan about people not knowing since it's a giant, red, ominous looking AoE that in every other instance of the game would scream BAD BAD BAD DO NOT STAND HERE.
Nevermind the fact that it's nigh indistinguishable from the default color the game sets offensive AoEs to - and every other game. I have mine set to bright pink to combat this, but still.
I know that some people might respond with how it's just a part of the game and how it's easy to recognize once you know how to recognize it (redundant, but anyway), but for the sake of healers not having to explain to every. single. group. that they run with. to not run out of the Earthgore proc, please. Consider it.